If "SYS" is displayed in the LCD section of the instrument panel cluster after installing a new (aftermarket) stereo, you will need to do the following:
1. Buy two 1,000 Ohm 1/2 watt resistors. [Radio Shack part # 271-023. They sell them as a 2pk for .29 cents.]
2. Disconnect the negative battery cable.
3. Remove the receiver.
4. Connect one end of both resistors to ignition power. (Yellow wire in the car)
5. Connect the other end of one resistor to the purple/white wire in the car.
6. Connect the other end of the second resistor to the grey/black wire in the car.
7. Cover all connections and completely cover the resistors.
8. Reconnect the negative battery cable.